Genghis Barbie is a "post post-feminist feminist" French horn quartet that plays breathtaking renditions of Somebody to Love, Kiss from a Rose and Janelle Monae's 57821. Oh, and Thong Song.
The brass quintet Canadian Brass is both venerable--it's been around 38 years--and prolific--its discography is as long as your arm. While they often play classical arrangements, they also mix in jazz and blues, along with a complement of showmanship and humor. (Also, they play Flight of the Bumblebee on the tuba.) [Mouseover for titles.]